Sunday, September 6, 2009

IPPS International 2009 Paper!

Well I think I finally finished it, it was hard to limit the page number to only 7!  I am very long winded when I write.  Then I looked at the Proceedings from last year and noticed most people had only 3 pages, so I went and chopped some more down to 5 as to not be a page hog!  I hope that this gives some further insight to what we do here, please feel free to comment. 

The Good, The Bad and The Ugly.  Young Plant Production in Magnolia, Texas at Magnolia Gardens Nursery.

April Herring
Magnolia Gardens Nursery Liner Division, 18810 Turtle Creek Lane, Magnolia, Texas 77355


Magnolia Gardens Nursery is a nursery in Magnolia, Texas that specializes in young plant production through the use of tissue culture, in particular that of numerous Nandina domestica cultivars.  Young plant production comes with many rewards but there are many challenges to overcome to reach those rewards.  These challenges include deciding what plants to produce, determining the best production protocol, acclimization and finishing, and finding innovative ways to deal with a slow economy.   One of the biggest rewards is the discovery of a new plant and having the ability to use tissue culture to bring it to market quicker than traditional propagation methods.  Many bridges must be crossed to reach this final step and each must be crossed with high success rates so that the end product is of good quality and ultimately, profitable.


What Plants Should We Produce?  To answer this question we first have to ask ourselves:

1.  Is the plant worthy?
2.  Can we grow it?
3.  Are we making enough profit on the item?
Before starting any new product we first trial it outside to make sure it is truly unique compared to other products already on the market making it worth growing.  Also this trialing period is a good time to note whether or not the plant can be grown in our climate.  Something else we consider is whether or not a potential new product is easy to propagate conventionally as the tissue culture process is costly. 
Once it is established that a plant is worthy, the next step is to determine if it can be produced with success.  Some plants prove extremely difficult to grow in the lab, such as trees.  Other plants don’t grow well in either the lab or the greenhouse and the losses involved are too high to make much if any profit.  An example of this for our lab would be Ensete ‘Maurelli’; by the time everything was said and done plant losses were 50% or more.  This does not account for space and labor losses this plant caused as well.  Other plants grow very well in the lab; it is the Texas climate that causes poor to no survival.  Phormium and Libertia are examples of this type of plant, which look fine in cooler months but cannot make it through the extreme summer months.
Lastly, we ask, are we making a profit on this item?  Some plants are worthy and we can grow them, it is other issues make them bad choices for production.  Bananas such as Musa ‘Dwarf Cavendish’ are examples of this.  Bananas is a great candidate for tissue culture but the problem was the amount of labor needed to keep the plants maintained in the lab, being 2-3 times more than a woody.  Also, the big sales season is in the spring so the rest of the year is spent on maintenance or subculturing the mother stock.  There are many reasons to produce a product or not, each plant must be looked at individually to make an informed decision.

How do we get a plant into a sterile environment?

There are many factors that come into play when deciding what steps to take in getting a plant clean of contaminates.  Plant type, plant age, the growing environment that the plants were in, time of year, and more all play large rolls into how successful the sterilization procedure will be.  Plants we commonly produce have a general sterilization procedure but even the same plant can have different results using the same procedure.  The best method is to decide the procedure used the day of initiation according to the plants appearance.  Tender plants can burn easily and plants that are more mature may need more sterilization.  A combination of Sodium Hypochlorite, Ethanol, along with sterile distilled water and Tween is used in our sterilization procedures.

How do we grow a plant in a sterile environment?

Once the plant is clean it is time to figure out what media it will best grow on.  To keep processes efficient we usually try and grow a new plant on media we already are using and making in large batches, pending the research shows it can grow on something similar.  Small batches of media are made for plants that we know our common media will not work on and for experimental media for plants that are not performing to our standards.
Not only must media be considered but the crop cycle must be decided as well.  Some plants will let you know very quickly how long their crop cycle is.  Yucca ‘Color Guard’, for instance, will start dying at about 4 weeks, if they are not transferred on time the crop will be lost.  Woody plants can survive longer than most herbaceous plants and some need to be subcultured less or they perform poorly when weaning.  The most common crop cycle is 6 weeks but many plants can go longer than this.  As the lab gets behind on transfers, which is common, we quickly learn what plants last the longest.


Plant produced in tissue culture become accustomed to living in a perfect environment and then they must be able to survive the great outdoors which has a higher light intensity, less humidity and for the most part in Texas, is hotter.  We help them as best we can with the transition by using a double shade system, black shade cloth on the outside of the greenhouse and Svensson® XLS firebreak screen on the inside to reduce temperatures.  Also we cover the plants with a plastic dome, which are purchased clear but are given a light coat of white spray paint to give even greater protection from the high light.  The domes serve another purpose as well by keeping the humidity high.  After a week of being covered the plants are uncovered to start to adjust even further to the drier air.  To keep the temperature cooler in the summer months a Kool Cell pad and fan system is used.  In the weaning area no fertilizer is used as to not burn the roots of the sensitive plantlets.  After around 4 weeks plants are moved to their final location before shipping.  These growing areas have high light levels and liquid feed is used in these areas.  Plants have the hardest time adjusting to the outside environment during our summer months, which can be very hot and humid.  Because of the harsh summer we must pick plants that can handle this rather than try to fight the climate.  Also we have to be very careful planting during extreme heat such as in June 2009 where we had 7 days straight above 100 °F (38°C).  Plants that are sensitive in the weaning process should be held in the lab when possible until the weather cools. 

How do we handle production in a bad economy?

A slow economy comes in cycles so one must be prepared for this to happen.  The most important thing we do is keep in contact with customers to see how they are doing, what products do they need and what orders will need to be cancelled.  Even with communication it is still hard to know exactly when things are going to come to a stand still and when things will start moving again.  There are several steps we take to keep plants in the pipeline so that we are ready when sales pickup.  Young plant production has a continuous pipeline of product being produced, once sales slow the numbers coming out of the pipeline must be adjusted.  The mother stock must always be maintained or subcultured even if product is not needed otherwise the crops will decline and eventually die.  We usually try and keep motherstock at predetermined inventory levels.  When subculturing any excess product produced will be rid of to keep the supply in check with the market demands rather than putting it into stage 3 production.  This is also a good time to weed out any weak plants and get crops in top-notch condition.  Discarding plants in the micro stage is the most cost efficient as the cost of planting and maintaining in the greenhouse can be considerable.  The flow of the pipeline will be slower but it should not stop completely so that there is product ready to go when sales pickup, if the pipeline is completely shut off it could take upwards of 20-30 weeks to get product ready for sales.  Ways of doing this include holding plants in a cooler at 40 °F (4.5°C) to slow down growth, holding plants on the shelf longer before sending to wean, holding plants outside longer by keeping in the weaning area longer and by decreasing fertilizer usage once they are moved to their finishing location.  Because sales are slow in a downturn eventually finished material must be discarded because the quality no longer meets our standards and most products have a limited shelf life no matter how much care is given to them.  As old plants in various stages of growth are rid of, new plants are replanted in hopes sales will pick up, keeping the pipeline full.


Producing plants is tricky as they are living and will not fit the factory production model.  This can cause much frustration at times, as plants seem to have a mind of their own.  For us there is no better reward than to discover a new product at the nursery and to then see it through to production, marketing and eventually sales.  It is the light at the end of the tunnel that drives us.


Young plant production comes with many challenges as most businesses do but there are many rewards to be enjoyed once these challenges are worked through.  At Magnolia Gardens Nursery we decide what plants best fit into our production model, fine tuning a selection of product that is in good demand, that will receive a fair price, and that we can produce with great success and quality.

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